Foam side panels in mini-cell bulkhead boats?

[BAD paddle]

L 'Edge, Blackfly, Silverbirch all seem to put some kind of foam side panel in their cockpits. Not so much in strap-outfitted boats. I'm assuming the reason is extra buoyancy; is there more to it?

[Wendy]

! gallon of water weighs 8 pounds, so adding sidewall foam eliminates space for water accumulation.

[Pierre LaPaddelle]

Further to Wendy's comment, boats not equipped with bulkhead outfitting often require more in the way of customizing: anchors, tiedowns, etc. -- a good reason for not expecting the factory to foam the side-walls. That said, once your outfitting is complete, I think it's a good idea to add side-wall foam.

Rick